The present invention pertains in general to means for restraining a child safety seat to a vehicle seat to facilitate the carrying of small children in vehicles with the protection afforded by existing child safety harness and seat arrangements and more particularly to an adapter means for employing portions of a preinstalled passive diagonal torso safety belt to restrain the child safety seat on the vehicle seat.
Child safety seats are generally known, as shown in U.S. Pat. No. 4,040,664, and may be positioned and held on a vehicle seat by passing the normally floor anchored lap safety belt about the seat and, in effect, buckling it in place on the seat just as a passenger would buckle himself into the vehicle seat. However, with the advent of different types of so-called "three point" safety harnesses, additional problems have occurred in using the existing seat belt arrangement for buckling the child safety seat into the vehicle seat. In one known prior art situation, where the chest belt and lap belt portions of the safety harness pass freely through the tongue plate connector employed for buckling the belt portions to a floor mounted retractor, a locking clip has been appended to the belt portions to in effect fix the tongue plate relative to the lap portion so that the lap portion of the safety harness could be wound over the seat belt and buckled in place very much as in the manner shown in said U.S. Pat. No. 4,040,664, the chest belt portion being merely passed behind the child seat with the lap portion extending over it.
More recently, so called "passive" safety belt harness arrangements have been considered for use in commercial vehicles wherein the safety belt is moved between positions of passenger restraint and passenger release through merely the opening and closing of the vehicle door, there being, however, no specific lap belt portion available for restraining a child safety seat in place. One such "passive" restraint system is illustrated in the co-pending U.S. application for Patent, Ser. No. 872,306 filed Jan. 25, 1978 and being assigned to the assignee of the within application. In that passive safety belt system, the passengers lower body portions are restrained in the event of sudden vehicle deceleration through the provision of knee pads positioned on the vehicle interior. Only the passenger's upper torso is restrained by a safety belt which extends diagonally from a floor anchored inboard of the vehicle seat to a guide means mounted on the vehicle door, the safety belt passing through the guide means to a door mounted safety belt retractor which winds and unwinds the belt during door opening and closing motions. In such a seat belt arrangement, it is not possible to use the preinstalled safety belt to hold or restrain a child safety seat in the associated vehicle seat.